Signaling apparatus



July 10, 1923.

W. L. WALKER SIGNALING APPARATUS Filed June 22. 1917 Patented July 10,1923.

WILLIAM L. WALKER, OI NEW YORK, N. Y., ASSIGNOB T WALKER SIGNAL ANDEQUIPMENT CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE.

SIGNALING APPARATUS.

Application filed June 22, 1917. Serial No. 176,299.

T 0 all whom it may concern Be it known that I, WILLIAM L. WALKER, acitizen of the United States, and resident of New York, in the county ofNew York and State of New York, have invented new and usefulImprovements in Signaling Apparatus, of which the following is aspecication.

This invention relates to electrical signal- 1 ing apparatus forreceiving sound disturbances and the like, whether above or below theaverage audible range and whether in code or otherwise, and moreparticularly the invention relates to submarine (iignaling apparatusadapted to detect sound isturbances beneath the surface of a body ofwater and to transmit the disturbances to a distant point.

Of the many types of apparatus heretofore proposed for submarinesignaling, most of them have comprised either a microphonic device or anelectromagnetic device for transforming the sound disturbances intoelectrical disturbances in order to transmit the signals from thereceiving device to a distant point. The electromagnetic devices havebeen more or less heavy and the moving parts have been adapted torespond readily only to wave disturbances throughout :1 limited range offrequencies. Moreover, the

electromagnetic devices have not been sulficiently sensitive to detectthe fainter disturbances such as the sound disturbances produced by adistant vessel. The microphonic devices have not been whollysatisfactory for the reason that they are inherently delicate andtherefore not adapted to reproduce heavy sound disturbances whichproduce a large movement of the sound diahragm or other sound responsivedevices. oreover, the microphonic devices have not been capable ofdistinguishing between sounds of different characters and of widelydifferent intensities.

It is the principal object of the present invention to overcome thedisadvantages inherent in the above and other types of apparatus and toprovide means for receiving sound disturbances and the like, of whatevernature, which is exceedingly sensitive, which will respond todisturbances throughout an exceedingly wide range of frequencies andMensities, which wil readily distinguish n the various kinds of soundsuch as 58 Ski bounds produced by submarines of different types, surfacevessels of different typesand sizes, code signals of various intensitiesand frequencies and which is also adapted to receive and reproducespeech. Another object of the invention is to control the pressurewithin a sound-box so that as the sound-box is submerged in a body of water with the outer surface of the sound dia phragm in contact with thewater the pressure of the water on the outside of the diaphragm iscounterbalanced by the pressure produced on the inside of the sound-box,the ressure within the sound-box preferably ing regulated automaticallyas the soundbox 1s raised and lowered in the water either mechanicallyor due to the rolling of the vessel.

Other objects of the invention are to provide signaling apparatus of thecharacter referred to which has a sound diaphragm unobstructed on theoutside, which has an adjustable electrode connecting with the diaphragmon the inside, which has a connection between the electrode anddiaphragm such as to permit lateral movement of the electrode,relatively to the path of vibration of the diaphragm, and which has auni ue electrolytic cell associated therewith. ill other objects are toreduce the length of the connection between the diaphragm and movableelectrode, in apparatus of this character, to reduce the inertia of themoving parts, to dispose the movable electrode largely in a gaseousmedium instead of a. liquid medium, thereby to reduce the resistance tomovement to increase the size of the diaphragm and yet to minimize theweight of the diaphragm, etc.

In the accompanying drawings,--

Figure 1 is a central vertical section of one embodiment of myinvention, parts being shown in elevation;

Figure 2 is an enlarged front elevation (that is, looking from the rightof Fig. 1) of the pivoted electrode shown in Fig. 1;

Figure 3 is an enlarged sectional view of the connection between thepivot lever arm and the diaphragm;

Figure 4 is a diagrammatic view of a modifiel form of electrodes;

Figure 5 is-a vertical transverse section through the hull of a ship,showing one manner of applying my improved apparatus to a ship forsubmarine signaling or detect ing purposes; and

Figure 6 is a plan view of the electrodes,

in general comprises a sound-box 1, which;

is preferably of cylindrical contour having a cylindrical wall 2 and endwalls 3 and 4,

a diaphragm 6 and opposed electrodes 7 v and 8, one of which isconnected to the diaphragm so as to be moved thereby. The diaphragm 6may be mounted on the soundbox in any suitable manner, but it ispreferably mounted in an opening 9 by means of a ring 11 secured to thesound-box around the opening 9 by means of bolts 12, the diaphragm beingclamped between the soundbox and the ring and packing washers 13 ofrubber or other suitable material being disposed if desired between thediaphragm and the housing and ring respectively. In the rear wall 3 ofthe housing an opening is preferably providedto give access to theinterior of the sound-box from the rear, this opening normally beingclosed by the cover 14.

At the bottom of the sound-box is provided a circular depending flange16, and into this flange is threaded a cup 17 which is adapted tocontain an electrolytic fluid. In order to revent the electrolytic fluidfrom contactmg with the cup member 17, which is preferably of metal, acup of insulation 18 may be fitted into the cup 17. Likewise, a disk ofhard rubber 19is preferably placed over the top of the cups 17 and 18 toprevent the electrolytic fluid from contacting with the .metallic partsdisposed above the cups 17 and 18. A washer 21 may, if desired, bedisposed between the disk 19 and the lower wall of the sound-box inorder to insure a tight fit between the cup members and the sound-box.

Mounted in the sound-box on the bottom thereof is an insulation member22 in which is mounted a'metallic contact plate 23, the contact platebeing secured to the member 22 by means of ascrew 24. Extending throughthe contact plate 23, insulation member 24, and an opening 26 in thebottom of the sound-box, thence through an opening in the disk 19 intothe electrolytic cup, is an electrode-7. This electrode preferably has asurface of revolution, the surface being concentric with thelongitudinal axis of the electrode, and in the preferred embodiment ofthe invention illustrated in the drawings, this electrode is cylindricalin. contour. The electrode is mounted in electrical contact with thecontact plate 23 and is preferably an opening in the lever arm 28, theshaft 27 having a peripheral groove 29 around its central portion andhaving conical recesses axially disposed in its opposite ends. A screw31 is threaded into an opening 32 in the lever arm 28 so as to engagethe groove 29 of the shaft 27 and hol the lever arm tightly in positionon the shaft 27. Bearing screws 33 are threaded through lugs 34projecting upwardly from member '22 into engagement with the ends ofshaft 27, the conical points 36 of the screws fitting into conicalrecesses in the shaft. The lugs 34 also preferably have portions 37which surround the ends of the shaft 27 which prevents the lubricant,such as graphite grease, in spaces 40 from coming out. Lock-nuts 38 areprovided to hold the pins 33 in the adjusted position. If it is desiredto insulate the electrode 7 from the sound-box, a layer of varnish orother suitable insulating material is provided between the member 20 andthe sound-box.

Dwing to the fact that the lever 28 is pivotally mounted in thesound-box its upper end, which travels in the arc of a circle, willnecessarily have some vertical movement. The diaphragm is mounted tovibrate horizontally. Consequently I referably provide means forconnectlng t e upper end of the lever arm 28 to theuiiaphragm which isadapted to permit some movement of the upper end of the lever armtransversely of the direction of vibration of the diaphragm. Thepreferred means for this purpose, whlch is shown enlarged in Fig. 3,comprises a sheet 39 of flexible material such as steel, which ismounted in slots 41 disposed in alinement in the opposing ends of thelever 28 and the stud 42 mounted on the diaphragm 6. The sheet member 39may be connected to the members 28 and 42 by means of screws 43, sheetsof insulating material 44 being provided between the member 39 and themembers 28 and 42 if it is desired to insulate the lever 28 from thesound-box 1.

The electrode 8 is preferably shaped as shown in Fig. 1 so that themajor portion of the electrode will be dis osed at some distance fromthe electrode and so that the lower portion of the electrode 8 willextend into proximity with the electrode 7. The electrode 8 ispreferably formed as a thin blade and the edge 5 of the electrode facingthe electrode 7 is preferably sharpened so as to present a more or lesssharp edge to the electrode 7. Electrode 8 is mounted in a slot 46 inthe lower end of the lever 28 by means of screws 47. The openings in theelectrode 8 for receiving the screws 47 are preferably elongatedhorizontally so that the electrode may be adjusted to and from theelectrode 7 on the lever arm 28. The electrodes are preferably formed ofdissimilar metals, such that when the electrodes are immersed in asuitable electrolytic fluid such as indicated at 48 a galvanic currentwill be set up between the electrodes as more fully described in myformer a plication. Suitable materials for the electro es are zinc andplatinum, and a suitable electrolytic fluid is sulphuric acid althoughany other suitable combination of metals and electrolyte ma be used. Theelectrodes are respective y connected to receiving circuits andindicating instruments, as described in the former application, throughconductors 49, one conductor being connected to electrode 7 through themedium of contact plate 23 and screw 24, and the other conductor beingconnected to electrode 8 in any suitable manner, as for example, by oneof the holding screws 30.

The top of the sound-box 1 is provided with an opening into which isthreaded a reducin nipple 51, a block of insulation materia 52 beingdisposed between the housing 2 and the collar 51. The insulationmaterial, which may be of hard rubber, serves to support the connectors53 and also to close the opening in the top of the soundbox, one or morewashers 54 of soft rubber bein inserted between the sound-box and mem er52 and between member 52 and reducing nipple 51, if desired in order toinsure a hermetic seal. In order to house the conductors 56 extendingupwardly from the connectors 53, a pipe 57 is preferably threaded intothe collar 51.

In order to balance the pressure of the water on the outside of thediaphragm 6 when the apparatus is submerged, a pipe 58 is preferablyarranged to communicate with the upper portion of the sound-box and toextend downwardly into the water below the sound-box, all as more fullydescribed in my prior application.

Certain aspects of the present invention are of utility not only inconnection with electrolytic fluids, but also in connection withmicrophonic electrodes, such as carbon button electrodes or a carbonpile. I have therefore illustrated in Fig. 4 a carbon electrode 7 and acarbon electrode 8' in contact with the electrode 7 these electrodescorresponding to the electrodes 7 and 8 in Fig. 1. When using this typeof electrodes an electrolytic fluid would of course not be employed, theelectrodes functioning merely microphonically.

However, the preferred type of electrodes is the electrol tic typeillustrated in Fig. 1, these electrod es functionin in accordance withthe following laws: he smaller the internal resistance of anelectrolytic cell the greater the current for a given external circuit.The magnitude of the internal resistance depends upon the size of theelectrodes, upon their distance apart and upon the s ecific resistanceof the electrolyte. The internal resistance is diminished by increasingthe area of the plates or by decreasin the distance between them. The E.M. of a cell gives rise to a current and also to the various potentialdifferences in all parts of the circuit. It may be said that currentflows by reason of the potential difference or equally that thepotential difference arises by reason of the current flow.

By predetermining the areas of the opposing faces of the electrodes theinternal resistance of the electrolytic cell can be pre determined tosuit the particular uses for which the apparatus is intended. Moreover,the sensitiveness of the apparatus can be regulated by varying thedistance between the electrodes and by suitably determining thecharacter of the electrolyte. When sound waves are impinged upon thediaphragm 6, the lever arm 28 and electrode 8 carried thereby areoscillated back and forth, thereby varying the internal resistance ofthe electrolytic cell, and ultimately actuating the indicating orrecording instrument connected to the conductors 56 either directly orthrough an audion, as'in my prior application. In this connection it isto be noted that better results are obtained by balancing the externaland internal resistance of the electrolytic cell. That is, theresistance of the conductors 49 and 56 and other portions of theexternal circuit should be approximately equal to the internalresistance of the electrolytic cell. By varying the length of theelectrode 8, as b substituting elec trodes of different lengt s, thesensitiveness of the apparatus can be varied. In general the apparatusis more sensitive the greater the ratio of the length of the lever armbelow the pivot to the length of the lever arm above the pivot.

In operation the electrodes will become disintegrated more or lessrapidly, the disintegration taking place almost exclusively in theregion of the opposing surfaces of the electrode. In order to correctfor the increased gap'between the electrodes produced by disintegration,one of the electrodes, namely, the electrode 7, is given the cont-our ofa cylinder. By rotating the electrode 7 a slight amount a new area maybe resented to the edge 5 of the electrode 8.

, oreover, the electrode 8 may be adjusted toward the electrode 7 bymeans of screws 47 to compensate for such disintegration.

My improved apparatus may be employed either in the manner disclosed inmy ormer application or as illustrated in Fig. 5, for example. Whenemployed as described in the prior application the apparatus is loweredinto the water to a suitable depth, say twenty-five feet, and by virtueof the water rising in pipe 58 the pressure within the sound-box can bemade equal to the premure of the water on the outside of the sound-box.In this way the diaphragm 6 can be made very thin, and for the samereason it'may bemade much greater in diameter for a given thicknessinasmuch as it does not have to withstand the pressure of the water. Inthis way the weight of the vibrating parts can be made much less and thesensitiveness of the apparatus can be materially increased. Owing to thefact that the pivoted electrode is disposed within the sound-box insteadof on the outside of the box, the lever arm may be made considerablyshorter and therefore considerably lighter. With the lever arm disposedwithin the sound-box the outer surface of the diaphragm is wholly uncovered to the action of sound waves.

In applying my improved apparatus to a ship it is preferably mounted onthe inside of the hull of the vessel with the diaphragm exposed to thewater throu h an opening in the hull as illustrated in ig. 5, theapparatus being disposed beneath the water level W. The pipe 58connecting the upper portion of the sound-box with the outside of thevessel may be extended u wardly above the level of the sound-box in t eform of a loop, as shown in Fig. in which event the water may rise inpipe 58 to a point above the sound-box. A valve 60 is referably providedto close the pipe 59 or the purpose of making repairs, and an airconnection and valve 61 may, if desired, be connected to the loop ofpipe in order to force air or other gas into the sound-box underpressure to regulate or supplement the pressure produced by the waterrising in pipe 58'. By virtue of the pipe 58 extending above thesound-box in the form of a loop, the pipe may be made of small internaldiameter and still contain a sufiicient uantity of air or other gas tobe compressed by the water rising in the pipe. When the pipe is ofrelatively small diameter the resistance which it offers to the waterwill be relatively larger, thereby to prevent a too rapid rise and fallof the water therein due to rolling of the vessel. Furthermore, whenusing a small pipe water will enter the vessel at a slower rate in theevent of the pipe being broken.

When employing the ap aratus as illustrated in Fig. 5 the electro yticcup 17 may be arranged to communicate with the exterior of the vessel,as for example, through a pipe 62 and valve 63. In this way salt watermay be admitted to the electrolytic cup and employed instead ofsulphuric acid or other electrolyte as the electrolytic solution. Bysuitabl regulating the pressure in the sound-box t e liquid may bepermitted to rise in cup 17 through connection 62 only to substantiallthe level of the liquid shown in Fig. 1. en water is permitted a to risein on 17 through pipe 62 the pressure in the soun -box is so regulatedthat the water will only rise to the desired height in the cup, thewater rising in pipe 58 to the same height.

In Fig. 5 I have also illustrated means for cutting off the sound-boxfrom the outside of the vessel, this means comprising a valve 66disposed in the short passage 67. In this way the passa e may be closedwhile the diaphragm is icing replaced or repaired. Moreover, the passage67 affords a pocket adapted to hold a quantity of relatively quiet waterwhile the vessel is being pro-' and its other erid connected to theinner side of the diaphragm so that movement of the diaphragm producesmovement of the one electrode relatively to the other electrode.

2. In apparatus of the character described, the combination of a soundresponsive member, a liquid container current carrying liquid in saidcontainer, a pair of electrodes immersed in said liquid in acedrelationship, one of the electrodes ing movable with relation to theother electrode, and means for positively connecting the said one of theelectrodes to the diaphragm so that it is moved relatively to the otherelectrode by movement of the diaphragm.

3. Submarine signaling apparatus comprising a housing having an openinin one side thereof, a diaphragm moun in the opening, current carryingliquid in the lower rtion of the housing, a movable electrod disposed atleast in part in the housing with its lower end immersed in said liquid,and means for 'tively connecting the electrode with the mner side of thediaphragm.

4. ubmarine signaling apparatus com prising a housing having an openingin one side thereof, a diaphra mounted in the opening, a liquidcontainer secured to the in one lower portion of the housing, currentcarrying liquid in said container, electrodes extending downwardly intothe li uid, one of the electrodes being movable, an means for positivelyconnecting the movable electrode with the diaphragm 5. In apparatus ofthe character described, the combination of a housing having an openingin one side thereof, a soundresponsive diaphragm mounted in the opening,a pair of opposed electrodes disposed in the housing, and a lever armpivotally mounted in the housing and having positive connection to thediaphragm, the lever arm serving to connect the diaphragm and oneelectrode so that movement of the diaphra'gm produces movement of theone electrode relativel to the other electrode along a path parallel tothe movement of the diaphra 6. gi gnaling apparatus comprising a daphragm, means for supporting the diaphragm, a lever arm, means forpivotally supporting the lever arm, flexible means for itivelyconnecting the lever arm to the iaphragm so that movement of thediaphragm in either direction produces movement of the lever arm aboutits pivotal support, the lever arm carrying an electrode thereon, asecond electrode mounted in proximity to the first electrode, and meansfor regulating the distance between the electrodes.

7. Signaling apparatus comprisin a housing having an opening in one sie, a diaphragm mounted in the opening, an electrolytic cell secured tothe bottom of the housing, a pair of electrodes mounted in the housingand extending into the cell in spaced relationship, means for connectingone of the electrodes to the diaphragm so that vibration of thediaphragm in either direction produces corresponding movement of theelectrode relatively to the other electrode, and means for insulatin theelectrodes from the housing and diap ragm.

8. Signaling apparatus comprising a housing having an opening in oneside, a diahragm mounted in the opening, an electrol ytic cell securedto the bottom of the housing, a pair of electrodes mounted in thehousing and extending into the cell in spaced relationship, means. orconnecting one of the electrodes to the diaphragm so that v1- bration ofthe dia hra produces movement of the electr e re atively to the otherelectrode, the housing being hermetically sealed, and means forregulating the fluid pressure within the housing.

9; Submarine signalingapparatus comprising a watertzht housing having anv r si a diaphragm mounted in the opening, a pair of electrodes disposedin the lower portion of the housing, means for connecting one of theelectrodes to the diaphragm so that'tnovement of the diathe outside sothat liquid may rise in thehousing around the electrodes when the housinis submerged.

10. ubmarine signaling apparatus comprising a water-tight housing havingan opening in one side, a diaphragm mounted in the opening, a pair ofelectrodes disposed in the lower portion of the housing, means forconnecting one of the electrodes to the diaphragm so that movement ofthe diaphragm produces movement of the electrode relatively to the otherelectrode, the lower portion of the hous' ing communicating with theoutside so that liquid may rise in the housing around the electrodeswhen the housing is submerged, and means for controlling the pressure inthe housing, thereby to regulate the depth of liquid in the housing.

11. Submarine signaling apparatus comprising a water-tight housinghaving an opening in one side, a diaphragm mounted in the opening, apair of electrodes disposed in the lower portion of the housing, meansfor connecting one of the electrodes to the diaphragm so that movementof the diaphragm produces movement of the electrode relatively to theother electrode, the lower portion of the ousing communicating with theoutside so that liquid may rise in the housing around the electrodeswhen the housing is submerged, and means for controlling the pressure inthe housing, thereby to regulate the depth of liquid in the housing, thelatter means comprising a tubular chamber communicating with the upperportion of the housing and extending below the housing intocommunication with the exterior so that liquid may rise in the chamberand compress the fluid in the chamber when the ap ratus is submerged.

12. ignaling apparatus comprising a vessel adapted to contain anelectrolyte, two electrodes in the'vemel having opposing surfaces, andsignal responsive means for moving the electrodes relatively to eachother, the surface of one electrode being relatively broad and thesurface of the other electrode being relatively narrow, said firstelectrode being adjustable whereby to permit presenting fresh surfacesthereof opposite said second electrode.

13. Signaling apparatus comprising a diaphragm, a pair of opposedelectrodes, and means including a flexible band rigidly joined at itsopposite ends to the diaphragm and one of the electrodes for connectingone of the electrodes to the diaphragm so that the electrode may havesome movement transverse to the direction of vibration of the diaphragm.

14. Signaling apparatus comprising a diaphragm, a pair of opposedelectrodes, and flexible means for connecting one of the electrodes tothe diaphragm so that the electrode may have some movement transverse tothe direction of vibration of the diaphragm.

15. Signaling apparatus comprising a diaphragm, a lever arm extendingalon one side of the diaphragm, means for connecting the lever arm tothe diaphragm, means for pivota-lly mounting the lever arm so.

that it is oscillated by vibration of the diaphragm, and a pair ofopposed electrodes one of which is carried by the lever arm so as to bemoved relatively to the other electrode by movement of the diaphragm andlever arm, the connection between the diaphragm and lever arm comprisinga flexible strip of material arranged to permit lateral movement of thelever arm relatively to the direction of vibration of the diaphragm.

16. Submarine signaling apparatus com prising a sound box having anopening in one side, a sound responsive diaphragm over said opening, anair chamber communicating with the interior of the sound box and pointbelow the sound box so that water may risein th conduit to or above thelevel said housin upon opposite faces of the sound box thereby'tocounteract the water pressure; on the outside of the diaphragm.

18. Submarine signaling apparatus comprisin asound box having an openingin one si e,fa sound responsive diaphragm over said opening, an airchamber communicating with the interior of the sound box and openinginto the water outside the sound box, the air chamber extending abovethe level of the sound box and opening into the water at a point belowthe sound box, whereby the pressure of the water on the outside of thediaphragm may be counteracted, and means to regulate the amount of airtrapped in the sound box.

19. In combination in a signaling apparain its side provided with adiaphragm exposed to fluid pressure, a pipe having a loop extending to apoint substantially above and havin one of its ends in communicationwith the interior of the housing and its opposite end 0 ning into thepressure fluid, and a valve lfevice arranged substantially at thehighest point of said loop for admitting air under pressure into saidhousing for equalizing the pressure upon opposite sides of thediaphragm.

20. In a signaling system comprising a housing having an opening in itsside provided with a diaphragm exposed to fluid pressure, means forequalizing the pressure 0 the diaphragm coinprising a pipe opening atone end into said ousing and opening at its opposite end into fluidunder pressure, and means at an intermediate point in said pipe wherebyair under pressure may be admitted to or discharged from said housing.

Signed by me at New York, New York, this 12th day of June, 1917.

WILLIAM L. WALKER.

'tus comprising a housing having an opening a

